The new species of horned dinosaur (ceratopsian) was named based on fossils collected from Montana in the US and Alberta, Canada.
Mercuriceratops gemini was approximately 6 metres long and weighed more than 2 tonnes. It lived about 77 million years ago during the Late Cretaceous Period.
Mercuriceratops means "Mercury horned-face," referring to the wing-like ornamentation on its head that resembles the wings on the helmet of the Roman god, Mercury.
The name "gemini" refers to the almost identical twin specimens found in north central Montana and the UNESCO World Heritage Site, Dinosaur Provincial Park, in Alberta, Canada.
"Mercuriceratops took a unique evolutionary path that shaped the large frill on the back of its skull into protruding wings like the decorative fins on classic 1950s cars. It definitively would have stood out from the herd during the Late Cretaceous," said lead author Dr Michael Ryan, curator of vertebrate paleontology at The Cleveland Museum of Natural History.
"Horned dinosaurs in North America used their elaborate skull ornamentation to identify each other and to attract mates - not just for protection from predators. The wing-like protrusions on the sides of its frill may have offered male Mercuriceratops a competitive advantage in attracting mates," said Ryan.
"Mercuriceratops shows that evolution gave rise to much greater variation in horned dinosaur headgear than we had previously suspected," said Evans.
The new dinosaur is described from skull fragments from two individuals collected from the Judith River Formation of Montana and the Dinosaur Park Formation of Alberta.
The finding was published in the journal Naturwissenschaften.
